Dirt-collector for rectifiers.



S. W. FARNSWORTH.

DIRT COLLECTOR FOR RECTIFIERS. APPLICATION FILED NOV. 6. m4.

1 1 99,459 Patented Sept. 26, 1916.

G C C C C Fay! WITNTELSSES m Q Q INVENTOR i V Mg W J ATTORNEY- SIDNEY W.FARNSWORTH, OF PITTSBURGH,

PENNSYLVANIA, ASSIGNOR T wEsrINe- HOUSE ELECTRIC A ND MANUFACTURINGCOMPANY, CORPORATION OF PENNSYL- VANIA.

X DIRT-COLLECTOR r'on RECTIFIERS.

Specification of Letters Patent.

Patented Sept. 26, 1916.

Application filed November 6, 1914. Serial No. 870,609.

To all whom it may concern I Be it known that I, SIDNEY -W. FARNS-WORTH, a citizen of the United States, and a resident of Pittsburgh, inthe county of Allegheny and State of Pennsylvania, have invented a newand useful Improvement in Dirt-Collectors for Rectifiers, of which thefollowing is a specification.

My invention relates to evacuated vapor' apparatus provided withreconstructing liquid electrodes, and it has. for its object to providemeans whereby the surfaces of the liquid electrodes in apparatus of' thecharacter specified, maybe maintained free from foreigncsubstances atallntimes.

In the manufacture of mercury vapor rectifiers, extreme care is used tohave all por-' tions of theinterior of the container absolutely cleanand free from foreign sub.- stances. This is, however, a very difficulttask, especially with'rectifiersof large ca pacity provided with metalcontainers and with elaborate shielding'systems. Not only does dirtappear to lodge in minute recesses in the metal but also small portionsof the metal itself are torn off by the arc. The mercury vapor, inapparatus of the character. specified, is continually condensing on the.outer walls of the container and dripping back to the cathode pool andthis condensed mercury takes up dirt particles from all portions of thecontainer and washes them back into the cathode where they dis turb thecathode surface, and, by their vaporization, destroy the homogeneouscharacterof the arc itself. By my invention, I am able to prevent thereturn of dirt particles to the active portion of the cathode spot in asimple and effective manner.

Referring to the accompanying drawing, Figure 1 is a side view of ametal rectifier embodying my invention, partially insect tion andpartially in elevation; and Fig. 2 isan enlarged view of a portion ofthe. rectifier shown in Fig. 1, showing my invention in greater detail.

A container 3 of refractory imperviousmaterial, such, for example, assteel, is providedwith a solid anode. 4 and with a liquid cathode; 5,preferably of mercury. -An anti-splash plate 4, of the type describedand claimedin my application Serial No. 829,825, filed April 6, 1914,and assigned to the Westinghouse Electric & Manufacturing 85 Company, ispreferably placed upon thebottom of thecontainer 3 and is submerged bythe liquid-of the cathode 5, under normal conditions. A cathode ring ,6,of some refractory insulating material, such, for/example, as quartz, ismounted on the late 4 and serves to divide the cathode po 5 intovtwo'portions, a substantially circ a'rinner portion, upon which the arcis started and maintained byany suitable means, and an outer annularinactive portion. The mercury vapor of the arc condenses upon the sidewalls of the container 3 and drips into the annular inactive portion ofthe cathode I pool, carrying with it dirt freed from the walls. Thisdirt, in all instances, floats' upon the surface of the mercury becauseof the relatively high specific gravity of the latter. communicationbetween the inner and outer portions of the pool 5 through smallpassages under the edge of the ring 6, clean mercury is permitted topass from the lower portions of the inactive cathode 5 to the centralactive portion thereof in order to maintain the level of the latter Thestructure which has been described to this point is sufficient tomaintain the active portion of the cathode clean when the rectifier ismaintained in a stationary position as, for example, in a substation,but, when it is desired to mount rectifiers of the character-describedupon electric locomotives, as

is frequently the case, it is found that the violent blows andvibrations to which they are subjected cause mercury to splash directlyfrom the outer pool to the inner pool over the edge of the ring 6,carrying with it dirt particles. I accordingly mount two rings 8 and 9,preferably formed of metal, outside the ring 6 and attach them securelyin place, as for example, by welding them to the plate 4,. as shown at10. The rings 8 and 9'are provided with holes 7 and be-' low the surfaceof the mercury and staggered with respect to each other. A flat ring'11, preferably of metal, is attached to the ring 8, near its upperedge, in any suitable manner, such as byv welding, and supports a ring12 by suitable brackets 13. Ad ditional support may be given to therefractory ring '6 and also to the rings 8 and 11 by the use 'ofauxiliary braces 14 therebetween.

Consequently, by maintaining free By the use of the abovedescribedstruc- J the container and may return to the central portion of thecathode by means of the holes 7 and and under thering 6, but it isextremely difiicult for any mercury to be splashed over the upper edgeof the ring 6.

While I have shown my invention in its I preferred form, those skilledin the art will understand that it is susceptible of various minorchanges and modifications without departing from the spirit thereof andI accordingly desire that only such restrictions vshall be placedthereupon as are imposedby the prior art or are specifically set fort inthe appended claims.

I claim as my invention: 1 1. The combination with an evacuatedcontainer, of a reconstructing liquid elec-- trode therein comprising anactive arc-supporting pool and an inactive pool arranged.

to receive returning electrode material, a partition separating thesurfaces of said pools and permitting communication therebetween belowthe surfaces thereof, and baflle plates arranged above said inactivepool to prevent slopping thereof over said partition and into saidactive pool when said electrode is agitated; Y

2. The combination with an evacuated container, of a reconstructingliquid electrode therein, a ring of refractory material outer pool, saidring providing passages between said pools beneath its lower edge, andbaflle plates arranged above said inactive pool to prevent the sloppingof electrode material from Said inactive pool to said active pool overthe upper edge of said ring when said electrode is agitated.

3. The combination with an evacuated container, of a reconstructingliquid electrode therein, a ring of refractory material seated in saidelectrode, extending above the surface thereof and dividing saidelectrode into an active inner pool and an inactive outer pool, saidring permitting communication between said pools beneath its lower edge,and annular partition members mounted in said inactive pool and providedI with relatively staggered openings beneath the surface thereof.

In testimony whereof I have hereunto subscribed my name this 29th day ofOct.,

SIDNEY W. FARNSWORTH. Witnesses:

JOHN BIRRELL, B. B. HINES.

